Web supply means



March 24, 1959 K. F. NEWELL 5 1 WEB SUPPLY MEANS Filed Aug. 30, 1957 3 Sheets-Sheet l INVENTOR.

K T-IT'IEFPI 1 new 911 March 24, 1959 NEWELL I 2,879,063

WEB SUPPLY MEANS Filed Aug. 30, 1957 5 Sheets-Sheet 2 K. F. NEWELL WEB SUPPLY MEANS March 24, 1959 5 Sheets-Sheet 3 Filed Aug. 30, 1957 INVENTOR. Kenn 91h ETIELLI E11 United States PatentO WEB SUPPLY MEANS Kenneth F. Newell, Longmeadow, Mass., assignor t Package Machinery Company, East Longmeadow, Mass., a corporation of Massachusetts Application August 30, 1957, Serial No. 681,246

6 Claims. (Cl. 271-2.3)

The present invention relates to the handling and control of sheet material webs, with particular relation to the supply roll from which the web is drawn.

One object of the invention is to control the rate of rotation of a supply in accordance with variations in web feed in order that the web may at all times be maintained tight against any element over which it is trained.

A further object of the invention is to provide improved means for transversely positioning a web through control of the supply roll from which it is drawn.

The above and other related objects as well asthe novel constructional features of the invention will be apparent from a reading of the following description of the disclosure found in the accompanying drawings and the particular novelty thereof pointed out in the appendedv claims.

In the drawings:

Fig. 1 is a rear. elevation of a web feeding system embodying the present invention;

Fig. 2 is a section taken on the line IIII in Fig. 1;

Fig. 3 is a side'elevation, on an enlarged scale, of the-lower portion of the system seen in Fig. 1;

Fig. 4 is a fragmentary view showing. an alternate relationship of certain parts seen in Fig. 3;

Fig. 5 is a fragmentary view, on an enlarged scale, of a portion of Fig. 1;

Fig. 6 is a section takenon line VIVI in Fig. 3; and

Fig. 7 isa section taken on line-VII-VII in Fig. 3.

For the convenience of persons acquainted with the wrapping machine art thepresent invention is herein disclosed in a form which has been found suitable for wrapping machines of the type disclosed in US. Patent No. 1,986,422 and commonly known by the trademark, Transwrap, under which they are sold. However, it

will be understood that this is in noway a limitation on.

the use of the invention'which is of general utility inthe field of web supplying devices.

A common arrangement of supply rolls for wrapping machines of this type is illustrated in .Fig. 1. The arrangement seen therein is for a dual unit machine having two package forming mechanisms, one supplied with wrapping material. from the rolls'10, 12 and the other from the rolls 14, 16. The use of two rolls for each package forming mechanism provides a two ply bag, highly desirable in packaging many materials.

For purposes of the present invention it will only be necessary to deal with the rolls 14 and 16 supplying one of the package forming mechanisms and then detailed consideration will be given only .to the novel braking means provided for roll 16, such braking means being duplicated for the other rolls 10, 12 and 14.

A web W is drawn from the roll 14 by draw bars common to the type of wrapping machine referred to and well shown in the aforesaid patent. The web W passes over an idler roll 18, under a vertically reciprocable tightener roll 20, over an idler roll 22 and then under a further idler roll 24. A web W is drawn, by the same draw bars, from the supply roll 16 over an idler roll 26, under a vertically reciprocable tightener rollv 28, around idler rolls 30, 32, over idler roll 33 and then under idler 24, at which point the two webs W, W are superposed. The superposed webs are drawn upwardly from the idler roll 24, in a pulsating or intermittent manner by the aforementioned draw bars.

Since the pull on each web W, W is intermittent, the rolls 14 and 16 will be accelerated to supply the webs and then have a natural tendency to continue rotating when no wrapping material is being drawn into the wrapping machine. Accordingly, the present invention provides improved braking means for controlling the rotation of the supply rolls where a web is intermittently drawn therefrom.

A detailed description of the braking mechanism associated with supply roll 16 will now be given and can best be understood by reference to Figs. 1, 3 and 5. The same braking mechanism can be partially seen in Fig. 1 but is not described in detail. The supply roll 16 ismounted between flanges 34 on a shaft 36 which extends between vertical frame members 38, 40. These frame members are recessed as at 42 (Figs. 1 and 3) to receive the shaft 36. The right hand end (Fig. l) of this shaft is rotatably mounted on a pair of ball bearings 44 carried on the inner wall of frame member 40. A brake drum 46 is secured to the other end of the shaft 36 and is received by a pair of roller bearings 48 mounted in a block 50 secured to the outer wall of frame member 38. The shaft 36 and supply roll 16 are thus freely rotatable.

The brake drum 46 is provided with a peripheral groove 47 which receives a protruding member in the form of roll 49 (Figs. 3 and 7). This roll is mounted on a block 51, which block is captured between flanges 53, 55 on a rotatable jack screw 57. The jack screw is threaded into an L-shaped member 53 which is secured to the frame member 38. The block 51 is bifurcated to receive the outstanding portion of the L-shaped member to prevent rotation of said block when the jack screw 57 is rotated by its hand knob 61.

Thus since the shaft 36 is free to slide axially of its mounting means the knob 61 may be rotated to obtain a correct positioning of the supply roll 16 in order to obtain proper transverse positioning of the web W and proper tracking thereof over the various rolls and elements around which it is trained.

A brake shoe 52 is disposed above the drum 46 and provided with a suitable friction material lining on its undersurface. The brake shoe has an upstanding portion 54 (Figs. 3 and 5) extending between a pair of plates 56 and captured therebetween by a bolt 58 which passes through a slotted self-centering arrangement in said plates. These plates 56 are pivotally mounted on a pin 60 extending from a bar 62 and not the frame member 38 (see Fig. 5). frame 38 by a screw 64 threaded therein. Spacing collars 66, 68 facilitate the pivotal mounting of the plates 56 and a locking collar 70 retains them on the pin 60.

In normal operation of this braking device the pin 60 serves as a fixed center for pivotal movement of the plates 56. This is by reason of a spring 72 extending be tween a screw 74 threaded into the frame 38 and a screw 76 on the bar 62 and urging said bar in a down-- ward or counterclockwise direction. The position ofbar 62 (and pin 60) is adjustably established by a screw 78 threaded through bar 62 and engaging a block 80 secured to the outer wall of frame member 38.

Also secured between the plates 56- is a bar 82 by means of screws 84. It will be noticed that the upper screws 84 pass through slots in the plates 56 to enable angular adjustment of the bar 82. The angularly disposed portion of bar 82 carries a weight 86 which is The bar 62 is pivotally mounted on the slotted to overlie said bar 82 and provided with screws 88 for clamping said weight thereon.

The above-described mounting means for the brake shoe 52 are particularly adapted to swing clear of the brake drum 46 to facilitate replacement of the supply roll 16. The spring 72 has an over-the-center relationship by means of which it maintains the bar 62 in the operative position seen in Fig. 3. Said over-the-center relationship also permits the bar 62 to be swung about the screw 64 and maintained in an upper position illustrated in Fig. 4 with the spring 72 holding said bar 62 against a stop screw 87 threaded into the frame 38. The brake shoe 52 and all parts associated with the plates 56 may thus be maintained free and clear of the brake drum 46, permitting said drum and the shaft 36 to be removed from the machine in order to mount a new supply roll thereon. After the supply roll is replaced it is a simple matter to swing the bar 62 into its lower position and return the brake shoe 52 to its operative position.

The upper end of bar 82 is bent to overlie a roll 89 which is journaled at the upper end of a slotted bracket 90. A screw 92 clamps the bracket 90 at a desired point along the length of a bar 94 which extends through the slotted undersurface of said bracket. It will be noted that the bracket 90 offsets the roll 89 from the bar 94. The bar 94 is welded to a hub 96 which is pivotally mounted about a screw 98 threaded into a plate 100 (Fig. 6). The plate 100 is provided with horizontal slots which receive screws 102 for adjustably securing said plate to a strap 104. Screws 106 secure the strap 104 to the frame member 38 and to a further spaced, vertical frame member 108. The spacing between the frame members 38, 108 provides a guideway for purposes to be described shortly.

A bar or actuating lever 110 is welded to the hub 96 and extends downwardly therefrom. This lever is responsive to movement of the roll 28 known as the tightener roll which is mounted as follows. The roller 28 (Fig. 3) is in the form of a sleeve rotatably received by a shaft 112. At either end of the shaft 112 are pinned matching gears 114 which mesh with matching racks 116 secured to the frame members 38, 40. A collar 118 is provided on the outer end shaft 112 and enters between the guideway provided by the spaced frame members 38 and 108. A similar guiding arrangement (not shown) is provided at the other end of the shaft 112 between the frame member 40 and still another vertical frame member.

As will be seen from Fig. 3, when roll 28 is in its lowermost position the lever 110 bears against the collar 118 and is in an extreme clockwise direction. This is an extreme position shown for illustrative purposes and not a normal operating position as will later appear. Under this condition the bar 94 is in its lowermost position and the roll 89 will be slightly spaced beneath the bar 82. The bar 82 is thus in an extreme counterclockwise position allowing full effect of the weight 86 in applying a braking force, by way of the shoe 52, on the drum 46.

When the web W is drawn into the wrapping machine the roll 28 will be raised and as it is so raised the lever 110 will be moved in a counterclockwise direction with respect to the pivot screw 98 and could assume the position shown in phantom where there was a quick pull on the web W. The bar 94 will be raised to the extreme position illustrated in phantom, lifting the bar 82 and with it the shoe 52 entirely away from the drum 46, so that the roll 16 is free to rotate and deliver the web therefrom at a maximum rate. The phantom position illustrated, again is not a position which would normally occur as will be brought out below.

The extremepositions of Fig. 3 have been shown to give a clearer picture of the manner in which the brake actuatingmeans operates. However, in normal operation the tightener roll 28 rides between a position one third and one half way up the guideway between the spaced plates. In the lower of these positions the shoe 52 applies a full braking force to the drum 46, and in the upper no, or substantially no braking force is applied to the drum 46. Thus as the web W is intermittently drawn into the Wrapping machine the tightener roll reciprocates each time between the above named positions. In so doing the web W is maintained taut and firm against the various rolls 26, 30, 32, 33 and 24. It has been found that in the case of a definite intermittent web feed where for a given cycle the web is fed only 50% of the time, that the supply roll should rotate for approximately the same portion of the cycle but in lagging timed relation to the pull on the web. This condition is exemplified in machines of the type of the said Zwoyer patent.

Thus in normal operation the roll 28 drops to the A position after each pull on the web W and in this position the brake shoe 52 positively stops rotation of the supply roll 16. Thereafter, when the web W is drawn into the wrapping machine, the roll 28 is gradually raised to the B position (which can vary with the inertia of the roll 16) and the brake shoe 52 gradually raised. This raising of the brake shoe 52 is more after the fashion of gradually releasing the braking pressure than a sudden release of all braking action. This gradual releasing action is obtained by the reverse leverage arrangement including both the low angle between the lever and the path of travel of the roll 28 and also the further reduction in resultant displacement provided by the lever arm distances about the centers at the screws 98 and 60.

This great reduction means that a fairly large movement of the roll 28 can be translated into delicate and sensitive gradations of the braking effect of the shoe 52.

Thus, when the wrapping machine pulls on the web W the roll 28 raises and the roll 16 will gradually begin to rotate. When the roll 28 reaches its upper B position it is preferable that some braking force is applied so that at all times there is controlled rotation of the supply roll 16. As the rate of the web W decreases the roll 28 drops and the braking force is increased. Thus shortly after the wrapping machine ceases to pull and draw said web, a complete braking force is applied to the drum 46 and rotation of the supply roll 16 is stopped until the web W is again drawn into the wrapping machine.

Having thus described the invention, what is novel and desired to protect by Letters Patent of the United States is:

1. In a device for supplying a web of sheet material in an intermittent manner, spaced vertical frame members, a shaft extending between said frame members and on which is mounted a supply roll from which the web is drawn, a brake drum at one end of the shaft, an upwardly open anti-friction bearing journal on each frame member, one for receiving the brake drum and the other for receiving the other end of said shaft, a brake shoe disposed above said drum, reverse leverage linkage mechanism comprising a pivotal member having self-centering means for mounting said brake shoe, a weighted lever extending from said pivotal member and overlying said brake shoe and tending to produce a braking force, and a pivotally mounted bell crank having one arm disposed beneath and engageable with said weighted lever and a second arm or actuating lever extending downwardly with a face at a low angle to the vertical, a pair of fixed idler rolls, a tightener roll therebeneath and vertically reciprocable in a plane intersecting the angularly disposed face of the actuating lever, said web being trained over the last three named rolls to form a loop, and means movable with said roll for engaging said actuating lever face to displace said lever in a direction causing said one hell crank arm to raise said weighted lever upon upward movement of said tightener roll and to allow said actuating 3 lever to move in a direction permitting the weighted lever to impart full force to said brake shoe upon the tightener roll reaching a lower limit of downward movement whereby full braking pressure will be applied to said brake drum to bring the supply roll to a complete stop.

2. In a device as in claim 1, wherein the said pivotal member is mounted on an arm which is in turn pivotally mounted on the adjacent frame and fixed stops are provided above and below said bar and an over-the-center spring arrangement is provided to maintain the bar against the lower stop with the pivotal member in the described operative position or against the upper stop with the pivotal member and brake shoe in a raised position permitting removal of the brake drum and shaft.

3. In a device as in claim 1, wherein the said pivotal member is mounted on an arm which is in turn pivotally mounted on the adjacent frame member, a fixed stop is provided beneath the arm and means are provided to adjust the position of the arm relative to the stop and thus obtain a desired relation between the brake shoe and brake drum.

4. In a device for supplying a web of sheet material at a variable rate, a shaft for mounting a supply roll from which the web is drawn, means for rotatably mounting said shaft, a brake drum secured to one end of said shaft, a brake shoe disposed above said drum, reverse leverage linkage mechanism comprising a pivotal member on which the brake shoe is mounted, a weighted lever extending from said pivotal member and overlying said brake shoe, a pivotally mounted bell crank having one arm disposed beneath and engageable with said weighted lever and a second arm or actuating lever extending downwardly with a face at a low angle to the vertical, a pair of fixed idler rolls, a tightener roll therebeneath and vertically reciprocable in a plane intersecting the angularly disposed face of the actuating lever, said web being trained over the last three named rolls to form a loop, and means movable with said roll for engaging said actuating lever face to displace said lever in a direction causing said one bell crank arm to raise said weighted lever, upon upward movement of said tightener roll and to allow said actuating lever to move in a direction permitting the weighted lever to impart increased force to said brake shoe upon downward movement of said tightener roll.

5. In a device for supplying a web of sheet material at a variable rate, a shaft for mounting a supply roll from which the web is drawn, means for rotatably mounting said shaft, a brake drum secured to said shaft, a brake shoe disposed above said drum, reverse leverage linkage comprising a pivotal member on which the brake shoe is mounted, a weighted lever extending from said pivotal member and overying said brake shoe and normally tendingto produce a braking force, and a pivotally mounted bell crank having one arm disposed beneath and engageable with said weighted lever, means for forming a loop in said web including a movable tightener roll, said bell crank having a second relatively long arm and means for guiding said tightener roll for reciprocable rectilinear movement in a plane at a low angle to said second bell crank arm, said bell crank being pivotal in response to movement of said roll to raise said weight lever upon movement of said roll reflecting a shortening of the loop formed therearound, said bell crank being pivotal in reverse direction to permit the weighted lever to impart full force to said brake shoe upon movement of said roll reflecting a shortening of the loop formed therearound.

6. In a device for supplying a web of sheet material at a variable rate, a shaft for mounting a supply roll from which the web is drawn, means for rotatably mounting said shaft, a brake drum secured to said shaft, a brake shoe engageable therewith, said brake shoe normally being held in braking engagement with said brake drum, a loop forming roll over which the web is trained, means for guiding said loop forming roll along a given path, a bell crank having one arm disposed at a low angle to the path of movement of said loop forming roll and displaceable in response to movement thereof, said bell crank having a second arm arranged to move said brake shoe away from normal braking engagement with said brake drum in response to movement of said roll towards a position reflecting a shortening of the loop of web material formed therearound.

References Cited in the file of this patent UNITED STATES PATENTS 950,473 Campbell et al. Mar. 1, 1910 1,166,948 Underhill Jan. 4, 1916 2,094,896 Knowlton Oct. 5, 1937 FOREIGN PATENTS 709,449 Germany Aug. 16, 1941 166,342 Germany Dec. 29, 1905 

